Optimize getAllPresent methods

This restores an optimization that was removed in #176 due to a bug in Java 8.
ben-manes · Feb 15, 2021 · 99c5711 · 99c5711
1 parent 0651746
commit 99c5711
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Showing 4 changed files with 39 additions and 41 deletions.
diff --git a/caffeine/src/main/java/com/github/benmanes/caffeine/cache/BoundedLocalCache.java b/caffeine/src/main/java/com/github/benmanes/caffeine/cache/BoundedLocalCache.java
@@ -43,7 +43,6 @@
 import java.util.Comparator;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.NoSuchElementException;
@@ -1946,33 +1945,33 @@ public boolean containsValue(Object value) {
 
   @Override
   public Map<K, V> getAllPresent(Iterable<?> keys) {
-    Set<Object> uniqueKeys = new LinkedHashSet<>();
+    Map<Object, Object> result = new LinkedHashMap<>();
     for (Object key : keys) {
-      uniqueKeys.add(key);
+      result.put(key, null);
     }
 
-    int misses = 0;
+    int uniqueKeys = result.size();
     long now = expirationTicker().read();
-    Map<Object, Object> result = new LinkedHashMap<>(uniqueKeys.size());
-    for (Object key : uniqueKeys) {
+    for (var iter = result.entrySet().iterator(); iter.hasNext();) {
+      Map.Entry<Object, Object> entry = iter.next();
       V value;
-      Node<K, V> node = data.get(nodeFactory.newLookupKey(key));
+      Node<K, V> node = data.get(nodeFactory.newLookupKey(entry.getKey()));
       if ((node == null) || ((value = node.getValue()) == null) || hasExpired(node, now)) {
-        misses++;
+        iter.remove();
       } else {
-        result.put(key, value);
+        entry.setValue(value);
 
         if (!isComputingAsync(node)) {
           @SuppressWarnings("unchecked")
-          K castedKey = (K) key;
+          K castedKey = (K) entry.getKey();
           tryExpireAfterRead(node, castedKey, value, expiry(), now);
           setAccessTime(node, now);
         }
         afterRead(node, now, /* recordHit */ false);
       }
     }
-    statsCounter().recordMisses(misses);
     statsCounter().recordHits(result.size());
+    statsCounter().recordMisses(uniqueKeys - result.size());
 
     @SuppressWarnings("unchecked")
     Map<K, V> castedResult = (Map<K, V>) result;

diff --git a/caffeine/src/main/java/com/github/benmanes/caffeine/cache/LocalAsyncCache.java b/caffeine/src/main/java/com/github/benmanes/caffeine/cache/LocalAsyncCache.java
@@ -28,7 +28,6 @@
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Set;
@@ -474,24 +473,25 @@ abstract class AbstractCacheView<K, V> implements Cache<K, V>, Serializable {
 
     @Override
     public Map<K, V> getAllPresent(Iterable<?> keys) {
-      Set<Object> uniqueKeys = new LinkedHashSet<>();
+      Map<Object, Object> result = new LinkedHashMap<>();
       for (Object key : keys) {
-        uniqueKeys.add(key);
+        result.put(key, null);
       }
 
-      int misses = 0;
-      Map<Object, Object> result = new LinkedHashMap<>();
-      for (Object key : uniqueKeys) {
-        CompletableFuture<V> future = asyncCache().cache().get(key);
+      int uniqueKeys = result.size();
+      for (var iter = result.entrySet().iterator(); iter.hasNext();) {
+        Map.Entry<Object, Object> entry = iter.next();
+
+        CompletableFuture<V> future = asyncCache().cache().get(entry.getKey());
         Object value = Async.getIfReady(future);
         if (value == null) {
-          misses++;
+          iter.remove();
         } else {
-          result.put(key, value);
+          entry.setValue(value);
         }
       }
-      asyncCache().cache().statsCounter().recordMisses(misses);
       asyncCache().cache().statsCounter().recordHits(result.size());
+      asyncCache().cache().statsCounter().recordMisses(uniqueKeys - result.size());
 
       @SuppressWarnings("unchecked")
       Map<K, V> castedResult = (Map<K, V>) result;

diff --git a/caffeine/src/main/java/com/github/benmanes/caffeine/cache/LocalLoadingCache.java b/caffeine/src/main/java/com/github/benmanes/caffeine/cache/LocalLoadingCache.java
@@ -22,9 +22,7 @@
 import java.lang.reflect.Method;
 import java.util.Collections;
 import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
 import java.util.Map;
-import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
 import java.util.function.Function;
@@ -64,24 +62,26 @@ default Map<K, V> getAll(Iterable<? extends K> keys) {
 
   /** Sequentially loads each missing entry. */
   default Map<K, V> loadSequentially(Iterable<? extends K> keys) {
-    Set<K> uniqueKeys = new LinkedHashSet<>();
+    Map<K, V> result = new LinkedHashMap<>();
     for (K key : keys) {
-      uniqueKeys.add(key);
+      result.put(key, null);
     }
 
     int count = 0;
-    Map<K, V> result = new LinkedHashMap<>(uniqueKeys.size());
     try {
-      for (K key : uniqueKeys) {
+      for (var iter = result.entrySet().iterator(); iter.hasNext();) {
+        Map.Entry<K, V> entry = iter.next();
         count++;
 
-        V value = get(key);
-        if (value != null) {
-          result.put(key, value);
+        V value = get(entry.getKey());
+        if (value == null) {
+          iter.remove();
+        } else {
+          entry.setValue(value);
         }
       }
     } catch (Throwable t) {
-      cache().statsCounter().recordMisses(uniqueKeys.size() - count);
+      cache().statsCounter().recordMisses(result.size() - count);
       throw t;
     }
     return Collections.unmodifiableMap(result);

diff --git a/caffeine/src/main/java/com/github/benmanes/caffeine/cache/UnboundedLocalCache.java b/caffeine/src/main/java/com/github/benmanes/caffeine/cache/UnboundedLocalCache.java
@@ -28,7 +28,6 @@
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
@@ -110,23 +109,23 @@ public long estimatedSize() {
 
   @Override
   public Map<K, V> getAllPresent(Iterable<?> keys) {
-    Set<Object> uniqueKeys = new LinkedHashSet<>();
+    Map<Object, Object> result = new LinkedHashMap<>();
     for (Object key : keys) {
-      uniqueKeys.add(key);
+      result.put(key, null);
     }
 
-    int misses = 0;
-    Map<Object, Object> result = new LinkedHashMap<>(uniqueKeys.size());
-    for (Object key : uniqueKeys) {
-      Object value = data.get(key);
+    int uniqueKeys = result.size();
+    for (var iter = result.entrySet().iterator(); iter.hasNext();) {
+      Map.Entry<Object, Object> entry = iter.next();
+      Object value = data.get(entry.getKey());
       if (value == null) {
-        misses++;
+        iter.remove();
       } else {
-        result.put(key, value);
+        entry.setValue(value);
       }
     }
-    statsCounter.recordMisses(misses);
     statsCounter.recordHits(result.size());
+    statsCounter.recordMisses(uniqueKeys - result.size());
 
     @SuppressWarnings("unchecked")
     Map<K, V> castedResult = (Map<K, V>) result;